Hydraulic transmitter with follow-up



Nov. 11, 1958 J. MERCIER ET AL 2,359,592

HYDRAULIC TRANSMITTER WITH FOLLOW-UP Filed June 29, 1.956 4 Sheets-Sheet 1 Nov. 11, 1958 J. MERCIER ETAL HYDRAULIC TRANSMITTER WITH FOLLOW-UP 4 Sheets-Sheet 2 Filed June 29, 1956 Nov. 11, 1958 J. MERCIER ET AL HYDRAULIC TRANSMITTER WITH FOLLOW-UP 4 Sheets-Sheet 5 Filed June 29, 1956 NEW 79 akl ll .l'fvi'llll! Ill, IIIIII ZI:

Nov. 11, 1958 J. MERclER ET AL HYDRAULIC TRANSMITTER WITH FOLLOW-UP Filed June 29, 1956 I 4 Sheets-Sheet 4- 1 I I l I l I I I l I I 11 120 I 122 126 134 133 124 7- I I I I35 I 12a P I 127 12a L o J I i i 138 JI L I L L I United States Patent .T

HYDRAULIC TRANSMITTER WITH FGLLOW-UP Jean Mercier and Bernard Mercier', New York, N. Y Application June 29, 1956, Ser'ial'No. 594,997

Claims priority, application France June30, .1955

41 Claims. (Cl. 60-97) This invention relates to a hydraulic.remote-steering system with -;a follow-up action more especially. forships rudder systems, in which-a receiveris steered bya rotary transmitter with the aid of a pump connected rotatably with the-transmitter.

The problem in such systems is the transmissionof the movements of the transmitter, for examplea steering wheel, to the receiver, for example the ships rudder or to a lever operating the rudder, underall operating conditions and completely free-asfaras possiblefrom interruption. Simpleelements should be used, the receiver should follow-the movements of the transmitter sensitively and it should bepossible toqincreasettheforce acting on the transmitter so tar as is required to ensure. that the receiver is definitelymoved in correspondence. .with the movement of the transmitter.

These problems are dealt with in such a system in which a receiver is operated with a follow-upaction bya steering transmitter which is rotatedin either direction; a

pumpis rotationally connected to the transmitter; liquid difierent purposes of use.

Examples of embodiments of -the.inventionvarerreproduced in the drawings, in which:

Figure 1 shows a remote steering system, .in .which the difference between the forces exerted Qnapumpby the transmitter adjust two control valves;

Figure 2 shows a system in which the torque exerted by the transmitter rotates a pivoted pump housing;

Figure 3 shows a system inwhich the torqueexerted by the transmitter swings a lever carrying theflpump;

Figure 4 showsa system with two remote steering-devices connected in parallel; i

Fig. 4 is a modification. of the embodiment .shownv in Fig. 4; and

Figure 5 shows a modification of the.system shown in Figure 4.

In Figure l a steering wheel formingtthe transmitter --is connected byanendless chain .11. and a roller. 12'to a pipes 15 or '16, which lead to operating. 2H1OiOIS.17 and 18. The operating motors comprises. cylindersprovided with plungers which are connected to,.the. operated.ele'

ment 19, shown in the form of a lever, by which: the rudder= is adjusted for steering.-

The-piston or other movableelement of the valve 14 is actuated by a rod which carries a roller 21. "The 2 roller '21 is pressed "against .theright hand run :ofthe chain 11 by a'spring22.

The device so faridescribed :can be v'used for steering when a force acts on the opposite left hand =run 'of the chain which is supported loosely round the steering :wheel 10 and the roller 12. This forcecorrespondsdothat exerted by the spring 22 and.can be exerted by aroller 23 which .is connected with the 'roller:21.'

The embodimentof Figure 1 also shows, inaddition to the control valve 14, an auxiliarywalvea2'4.actuated by the force exerted by the lleft hand:run ofztheachain between the: steeringrwheel.t10:and the :pump 13 with the aid of theroller.23.in;oppositionto;a .springt25. isThis auxiliary .valve .controls liquid pressur'emedium supplied from a source which is independent of .thezplumpl3.

This sourceis shown. as an electro-motor26. drivingaa 30 and 15 or 31 and. 16 under pressure, soxthattthe lever.

19 is actuatedby the operating motors29 and, [18;011529 and 17.

. If the steering wheeltltl. is stationary, .thetorcesexerted by the spring 22, 25 on the two runs of the chain lltiare equal and th'e rollers, 21, 23,.are, both at the-samesdistance from. the line ,which connects, the-axes 'of ;rotation ;of:,the wheel 10 and the"roller,12. ,Theivalves 14, 24-.are;then each in theneutral position intermediate ,theoperative positions. and the pipes 15,;16 ands30, 31 are closed.

When the transmitter -wheel' is'turned. clockwise,zithe run of. the chain onthe left'of the drawing istensioned by theresistanceof-the .pumpf13, so,that thespringlzz expands and the rod .20 with the piston or other, movable element of the valve 14 -is moved totheileft.

If the steering wheel v10 is turned ,in the opposite-dime tion, the right run of the chain 11 istensioned and m'oves the piston or other-movable: element ,ofithe valve 14;;to

the right. Oneof; the operating motors-17, or 18 iSrthUS always operated and the receiver lever 19 correspondingly swung as longsas the pump'l3vsupplies pressure liquid.

inapplications it ,is recommended that the ;opening' times of the valves;14,and 24 should be; adjusted-so 281.10

differ from another. whereby the valve24;will,..allow pressure liquid toxfiow through one of the:pipes...30;or31 only when the resistance of the pump 13 exceeds a certain magnitude. As a result, under-normal conditions only the valve 14 wi1lsupply fluid under pressure to motors 17, 18 to steer the ship, and as pipes30, 31 arelco'n nected through valve 24 tothe reservoir, 'the motor 29 will not block movement of leverf19. However when larger angular displacement of the rudder is required, movement .of wheel 10 an. additional amount will cause valve 24 to connectmotor29to. a source ,ofpress'urei to assist in the steering action.

Pressure liquid mediumfrotnthe. operating motorscan also flow Zthr0ugh the;.valves .14 and 24 -,back into the containers. 32 vor'33, from which;the;.corresponding pump is supplied. v

In the embodiment shown in: Figure 2, a-steering-wheel' 4l actuates=a pump 41 by-mea-ns of a -r0ller: 42. l he pump 41 is rotatably mountedon a shaft, which is situated near the axis of the roller 42.

The housing of the pump 41 carries an arm 43 which is connected with the piston or other movable element of a four-way valve 44 which'is biased by two springs 45 and 46 towards a central position which corresponds tothe neutral intermediate position of the movable element of the valve 44.

The whole device is disposed in a liquid tight casing which forms a liquid container; the pump and the valve are immersed in the liquid.

The valve 44 directs liquid under pressure to a single acting operating motor 47 for the rudder in cooperation with a return spring 48.

.When the steering wheel 40 is turned clockwise, the lever 43 is pressed downwards owing to rotation of the pump housing 41 and moves the piston or other operating member of the valve 44 in the same direction. If the wheel 40 is rotated in the opposite direction, the movements are opposite and the operating member of the valve is raised. According to its position the valve directs liquid under pressure into the upper part of the operating motor.47, so that the piston is moved downwards against the force of the spring 48, or releases the liquid pressure so that the return spring 48 forces the liquid enclosed in the motor. into the container through the valve.

When the valve is in the neutral position, that is when the steering wheel 40 is stationary, the pipe leading to the cylinder is blocked; the member connected as operated element to the motor 47 is thus held in the position into which it has been brought by turning the steering wheel. The steering wheel and the pump in the example shown in Figure 2 are connected by a chain, a belt or other fiexible' driving medium. Geared wheels may alternatively be used, in which case the pump must be mounted on a shaft the axis of which exactly coincides with that of the roller 42.

In the system shown in Figure 3, a steering wheel 50 rotates through multiplying gear, a roller 51 actuating a pump 52. All these members are supported on a lever 53, which swivels about an axis coinciding with the axis of rotation of the steering wheel, such assembly constituting a planetary (epicyclic) system. Return springs 54 and 55 tend tohold the lever 53 in its central position. The pump 52 is immersed in the liquid in a container 56.

The pressure liquid supplied by the pump 52 is supplied to a control valve 57, having a piston or other movable element connected to the lever 53. The pressure liquid is conducted by the valve either into the lower or upper part of a double-acting operating motor 58 according to whether the lever 53 deflects under the influence ofthe resistance to rotation of the pump 52 to the left or-to the right.

The piston of the operating motor 58 is connected by its rod to a lever 59 which represents the operated element of the remote steering mechanism. The cylinder end 60 of the motor 58 is fixed to an auxiliary valve 61 having its opposite end 62 pivotally mounted on a fixed support.

The valve 61 takes any one of three positions, the upper and lower positions depending upon the expansion or contraction of the operating motor 58. In the intermediate or neutral position, all the mechanism is stationary. A source 63 of pressure liquid independent of the pump 52 is connected to valve 61.

The piston of an auxiliary valve 64 is subjected to the pressure liquid supplied by the source 63 through the pipe 68 and to an opposing force exerted by a spring 65. y

tor 66 to be connected to the valve 61 and to'be moved in either direction by pressure liquid from the source 63 according to the adjustment of the valve 61. With valve 64 in this upper position, the motor 66 is not connected to the valve 57 and can only be supplied with pressure liquid from the source 63 when the valve 61is adjusted upwardly or downwardly by the operating motor 58 which is then controlled by the valve 57. The two operating motors 58, 66 thus cooperate to rotate the lever 59 in one direction or the other.

When the pressure of the liquid from source 63 drops below a certain value, the piston of the auxiliary valve 64 moves downwardly under the action of the spring 65, the pipes connecting the valve 61 to the operating motor 66 are closed and connections from the valve 57 to the motor 66 are opened. The valve 57 may then direct liquid from the pump 52 to both operating motors 58, 66 so that the two motors cooperate to rotate the lever 59 in either direction.

When the steering wheel 50 is rotated clockwise, the resistance to rotation of the pump 52 swings the lever 53 to the left, so that the piston or other movable element of the valve 57 also moves to the left. In this position the lower part of the lifting motor 58 is put under pressure by the liquid supplied by the pump 52. The piston of motor 58 is therefore pushed into its cylinder and the movable element of the valve 61 is moved downwards so that the upper part of the lifting motor 66 is also subjected to pressure from pump 52, and the two motors cooperate to rotate the lever 59 in a clockwise direction.

When the steering wheel 50 is turned in an anticlockwise direction, the two motors similarly cooperate to rotate the lever 59 in an anti-clockwise direction. If, for example. the lower part of the operating motor 58 is under pressure. the upper part of the operating motor 66 is charged with pressure medium and conversely.

In the system shown in Figure 4, a steering wheel 70 actuates simultaneously two pumps 71 and 72, positioned on a lever 73 which can rotate about an axis, which coincides or nearly coincides with the axis of the steering Wheel 70.

The lever 73 is connected with, so as to operate, two four-way valves 74 and 75, each of'which is supplied from one of the pumps 71 or 72. Containers 76 and 77 for the liquid medium are connected to these pumps. Two springs 78 and 79 tend to hold the lever 73 in its central position, in which the pistons or other movable elements of the valves 74 and 75 take up their neutral position.

For reasons of safety, a second steering unit 80 (steering wheel, pump and valve) is provided and connected in ,lparallel with the right side of the first described steering unit.

The valves 74, 75 are connected through pipes 81, 82 with auxiliary operating motors 83, 84 respectively. The plungersin these motors are connected to a lever 85, which forms the operated element of the remote steering mechanism. The cylinders of the motors are engaged by springs 86, 87 which also engage an auxiliary lever 88, rotatable about a fixed axis 89. The auxiliary lever 88 actuates two valves 90 and 91 which control pressure liquid supplied from a liquid pressure system 92 independently of the pumps 71 and 72.

The pressure system 92 is duplicated for reasons of safety and includes two pumps 93, 94 each associated with a hydraulic pressure accumulator 95, 96; each part of the system 92 is connected with one of the valves 90 or 91 previously referred to.

Each of the valves 90, 91 controls one of the doubleacting main operating motors 97, 98 which also act on the operated element of steering lever 85. If desired, the motors 97, 98 which are illustratively shown as hydraulic jacks, may be replaced by rotatable hydraulic motors 97', 98', as in Fig. 4 which drive a gear 97 secured to the shaft 98", which mounts lever 85. The motors have ports a, b and g, b' and when fluid under pressure is '85 is adjusted in one direction. 7 are so connected to the operating motors 97 and 98 that applied to ports a" and" b", for e 98' will rotate in a clo'ckwi'sedirection to turn ear97 and shaft 98" in a counterclockwisedirection.

There is further provided as an additional safety precaution, a reversible pump 100. Alterations of the position of the lever 88 influence through a rod; 99, the amount and direction of pressure liquid supplied by the reversible pump 100 to the additional operating motors 101 and 102 which cooperate with the operating motors 98 and 97.

When the steering wheel 70 is rotated in a clockwise direction, the pistons or other movable elements of the valves 74 and 75 are moved to the left and the valves put the auxiliary operating motors 83 and 84" under pressure, the pressure being relieved when the steering wheel is moved in an anti-clockwise direction. The opposite relationship may however be" followed". When the motors 83, 84 by this movement are thus put under pressure, the

auxiliary lever 88 is also swung clockwise and moves the pistons of the valves 90 and 91 as well as the rod 99 leading tothe reversible pump 100 whereby the main lever The valves 90 and 91 the upper part of one motor and the lower part of the other is always put under pressure.

When the steering Wheel 70' after such adjustment is stationary, the auxiliary operating motors 83, 84 are maintained in the positions to which they have been moved by the liquid retained in the pipes 31, 82. When the steering wheel 70 is adjusted in the opposite, that is the anticlockwise direction, the pressure in the pipes 81, 82 is relieved and the return springs such asthose associated with the valves 90, 91 and the pump 100 move the lever 88 in a counterclockwise direction and adjust the movable element of the valves whereby the operating motors 97, 98, 101, 102 may be energized to adjust the main lever 85 in the reverse direction.

The circuit of the pressure liquid in the reversible pump 100 is so arranged that the operating motors 101 and 102 always cooperate with the operating motors 98 and 97. If the instants of opening of the various valves are su1tably staggered, then it is possible, according to the magnitude of the difference of position between the steer ng wheel 70 and the receiving lever 85 to bring into operation only a few or even all of the operating motors. It is possible, for example, to operate the system in the following manner:

(a) When the first remote steering mechanism ad usts normally the auxiliary lever 88; the second remote steering mechanism 30 is brought into operation only when the first fails or is interrupted.

(b) When the auxiliary lever 88 swings, it first setsthe reversible pump 100 in action; if this is, not sufficient to turn the lever 85 as far as is'necessary, the valve 90 associated with the pump 93 is opened by further swing of the lever 83, so that the pump 93 comes into action.

(0) If even the force thus exerted together with that exerted by the pump 100 is not sufficient, then by further turning of the steering wheel 70, the difference of position between the lever 85 and 88 is increased still further thus opening the valve 91 associated with the pump 94, so that finally the whole available force is inserted in order to rotatethe lever 85, and thus for example the rudder connected with it, rapidly to the full extent desired.

In the example shown in Figure 5, the system is similar to that shown in Figure 4. A steering wheel 110jactuates two pumps 111 and 112, pivotally mounted on a lever 113 which is itself pivotally mounted and is connected by links to the pistons of two valves 114 and 115.

The outlets of the two pumpslll and 112 are connected to a pipe 116, which, on the one hand, is connected with the valve 114 and on the other hand with the left end of the cylinder of an auxiliary operating motor 117. The smaller "effective surfaceofthe piston of the motor 117 faces this left end. "The other end pie, both meters 91';

6 of" the lifting cylinder is. connected through. a pipe. 119 with the valve 114. '4

The valve is connected to a pipe 120,, which is supplied-by a pump 121 and a pressure accumulator 122 and leads into the left end of thecylinder of an auxiliary operating motor 123. The right end is connected by a pipe 124 with the valve 115. From each of'the valves 114 and 115, return pipes lead into liquid containers 125 and 126, respectively.

The piston rods of the auxiliary operating motors 117; and 123 are connected to the lever 127 to be controlled. The opposite ends of the cylinders are connected to an auxiliary lever 128.

This auxiliary lever is connected with the pistons of two further valves 129' and 130. The valve 129' is connected with the outlet of the pump 121 and with the corresponding return pipe; also by two power pipes with the two sides of an operating motor 131. The piston rod of this motor is pivotally connected to the lever 127', and the opposite end of the cylinder is connected to a fixed point of rotation.

The valve 130 is supplied by an independent pump 132 associated with a pressure accumulator 133 and a liquid container 134. From the valve 130, two pipes are led to an operating motor 138, the cylinder of which is connected to a fixed point of rotation while the piston rod is rotatably connected with the lever 127.

A reversible pump 135 supplies pressure liquid to a further operating motor 136 associated with the lever 127 in the same manner as the motors 131, 138. The amount and direction of the pressure liquid from the pump 13.5 are regulated by the auxiliary lever 128 through a rod 137.

The auxiliary operating motor 123 is always under pressure on one side, whereas the other side, towards which the greatest effective surface of the piston faces, is either put under pressure or relieved from pressure. The pressure liquid used for this control process is supplied from the pump 121, which at the same time supplies the pressure for the operating motor 131. In thecase of failure of the pumps 111 and 112, the control pressure can be taken in this manner from the independent pump 121, the control movement itself being derived from the lever 113 if the driving rollers of the pumps 111 and 112 are braked or held fast relatively tothe housing of the pump.

The different valves and operating motors can .cooperate in the same manner as was described in connection with Figure 4.

Instead of using the backwardly rotating movement of the pump itself, to operate valves, the transmitter can be connected with its pump by a planetary gear, of which one member is movable and allows a movement corresponding to that transmitted to act on the valve or valves.

It is desirable that at least one of the pumps should be operated by hand, so that the remote steering system or operated element .is independent of any supply of power. In the simplest case, the pump influenced by the transmitter reverses, according to its direction of rotation, the suction and pressure connections and acts directly on the members influencing the operated element, while a valve influenced by the pump controls a secondindependent source of pressure liquid.

The multiplicity of the elements used, which cooperate but as may be expedient can each effect remote steering at times independently, provides a great degree of safety. The degree of safety can also be increased by the connection of .a second operated element or steering group consisting of pump, valve and operating motor which may be connected in parallel with the first one and actuated by the same transmitter or a separate .transmitter and that the second group is connected automatically when interruption of operation of the first group takes place.

, As was to be seen from the examples, the invention can be carried out with very simple and cheap means; the device operates nevertheless with all required accuracy. For this reason the remote steering system is recommended especially for the steering of ships, where great resistance to any interruption of return movement is required.

As many changes could be made in the above constructions, and many apparently widely different embodiments of this invention could be made without departing from the scope of the claims, it is intended that all matter contained in the above description or shown in the accompanying drawings shall be interpreted as illustrative and not in a limiting sense.

Having thus described our invention, what we claim as new and desire to secure by Letters United States is:

1. Equipment for remotely controlling a member, said equipment comprising a transmitter rotatable in either direction, a pump operatively connected to said transmitter to deliver fluid under pressure upon rotation of said pump by said transmitter, hydraulically controlled means to effect actuation of said member in either of two directions, fluid control valve means operatively connected between the pump and said hydraulically controlled means and means responsive to the reactive forces produced by the resistance to rotation of the pump by the transmitter, to actuate said valve means.

2. The combination set forth in claim 1 in which the pump driven by the transmitter conveys fluid under pressure to said control valve means independently of its direction of rotation.

3. The combination set forth in claim 1 in which the pump driven by the transmitter conveys fluid under pressure to said control valve means independently of its direction of rotation, said valve has a control port operatively connected to said hydraulically controlled means and a pressure inlet port connected to said pump, and the direction of rotation of said pump by said transmitter controls the connection of said inlet port to said control port.

4. The combination set forth in claim 1 in which said pump is rotatable about an axis which lies near its driving axis and said valve means includes a valve having a movable element, and means operatively connected to said pump controls said movable element for actuation thereof upon angular movement of said pump about its axis.

5. The combination set forth in claim 1 in which a second source of fluid under pressure is provided, a second hydraulically controlled means operatively connected to i said member, valve means in circuit between said second hydraulically controlled means and said second source and means controlling said valve means and controlled by said first named hydraulically controlled means to actuate said second named hydraulically controlled means.

6. The combination recited in claim 5 in which additional hydraulically controlled means are operatively connected to said member and a reversible pump is connected to said additional hydraulically controlled means.

7. The combination set forth in claim 6 in which means are provided to effect action of said reversible pump prior to the operation of the second pressure source.

8. Equipment for remotely controlling a member, said equipment comprising a transmitter rotatable in either direction, a pump operatively connected to said transmitter to deliver fluid under pressure upon rotation of said pump by said transmitter, hydraulically controlled means to eflect actuation of said member in either of two directions, a second source of fluid under pressure to effect actuation of said hydraulically controlled means, fluid control valve means operatively connected between said sources of fluid under pressure and said hydraulically controlled means, and means responsive to the reactive forces produced by the resistance to rotation of the pump by the transmitter to actuate said valve means for connection of Patent of the said pump and said second source of fluid under pressure to said hydraulically controlled means. a

9. The combination set forth in claim 8 in which a flexible endless tension member operatively connects said transmitter and said pump, said valve means comprises at least one valve having a movable control element, and means operatively connecting said tension member with said movable element for movement of said movable element in accordance with the direction of rotation of said transmitter.

10. The combination set forth in claim 8 in which a lever is provided rotatable about the axis of rotation of said transmitter, said pump is mounted on said lever and said valve means includes a valve having a movable element operatively connected to said lever.

ll. The combination set forth in claim 8 in which said valve means includes a valve having a movable element actuated by said transmitter and resilient means are provided to restore said movable element to neutral position after actuation.

12. The combination set forth in claim 8 in which a storage container for liquid under pressure is associated with said pump and said valve means.

13. The combination set forth in claim 8 in which additional valves are provided supplied with liquid under pres sure from a separate and independent source and are operated directly or indirectly from the transmitter.

14. The combination set forth in claim 13 in which at least one of the additional valves is also actuated directly by the reactive forces between the transmitter and the pump.

15. The combination set forth in claim 13 in which at least one of the additional valves is controlled by the pressure liquid directed by said valve means.

16. The combination set forth in claim 13 in which when the action of the transmitter becomes stronger, the additional valves come into action in succession in such manner that the independent liquid pressure sources connected with the additional valves act in succession with increasing eflect to operate the rotatable member.

17. The combination set. forth in claim 13 in which means disposed on at least one of the additional valves renders the valve ineffective if the pressure liquid source connected with the valve does not supply sutficient pressure.

18. The combination set forth in claim 13 in which the actuating means for the additional valves are moved in dependance upon the difference of position between the transmitter and the member, said valves being arranged so that in the case of a small difference in position only one of the pressure sources is connected to the hydraulically actuated means and at increasing differences of position additional pressure sources are connected.

19. The combination set forth in claim 13 in which at least one of said valves has associated means which when the supply of liquid under pressure from one of said sources is insuflicient, automatically connects another of said sources.

20. The combination set forth in claim 13 in which at least one of the pressure sources is manually operated.

21. The combination set forth in claim 8 in which said hydraulically controlled means comprises a double acting cylinder and in which at least one valve supplies liquid under pressure to either side of the piston of said cylinder.

22. The combination set forth in claim 8 in which said hydraulically controlled means comprises a single acting cylinder and piston and in which at least one valve is connected with said cylinder and return springs are associated with said cylinder.

23. The combination set forth in claim 8 in which said hydraulically controlled means comprises at least one double acting hydraulic unit having a cylinder and a piston therein with one side of the piston having a smaller effective cross section than the other, said pump having a pressure port connected to said cylnider on the side of the piston having the smaller cross section, the other side of said piston being connected to the valve means associated with said pump.

24. The combination set forth in claim 8 in which a plurality of additional hydraulically controlled means are operatively connected to said member to supplement the action of said first named hydraulically controlled means.

25. The combination set forth in claim 8 in which a control valve is provided responsive to the reactive forces between the transmitter and the pump, an auxiliary hydraulic unit operatively connected to said member is controlled by said valve, an additional valve is controlled by said hydraulic unit, an independent source of liquid under pressure is controlled by said additional valve, and a second hydraulic unit actuated by the fluid from said source is also operatively connected to said member, both of said hydraulic units operating said member in the same direction.

26. The combination set forth in claim 8 in which said hydraulically controlled means comprises at least a pair of hydraulic units, said valve means comprises at least a pair of valves and a second pump is provided, said second pump, one of said valves and one of said hydraulic units being disposed in parallel with the first pump, valve and hydraulic unit, and is actuated by said transmitter.

27. The combination set forth in claim 8 in which a second transmitter and associated pump is associated with said first transmitter, and means are provided upon failure of said first transmitter to connect said second transmitter into the system.

28. The combination set forth in claim 8 in which a planetary system provides the connection between the transmitter and the pump, said system having means operatively connected to said valve means.

29. The combination set forth in claim 8 in which said hydraulically controlled means are rotatable motors.

30. The combination set forth in claim 1 comprising a second pump operatively connected to said transmitter to deliver fluid under pressure upon rotation of said second pump by said transmitter, second hydraulically controlled means to effect actuation of said member in either of two directions, second fluid control valve means operatively connected between said second pump and said second hydraulically controlled means and means responsive to the reactive forces produced by the resistance to rotation of the second pump by the transmitter, to actuate said second valve means.

31. The combination set forth in claim 30, in which at least one of the said valve means controls the actuation of the member through at least one another valve means controlling another source of fluid under pressure, said another valve means being responsive to an intermediate hydraulic cylinder controlled by said first named valve means.

32. The combination set forth in claim 31 in which an intermediate double acting hydraulic cylinder actuates the member.

33. The combination set forth in claim 30 comprising two pumps and means to deactuate one of said pumps.

34. The combination set forth in claim 5 comprising supplemental valve means responsive to another source of fluid under pressure and controlling the connections of the pump to hydraulically controlled means of differential area.

35. The combination set forth in claim 34, in which the active area of the hydraulically controlled means is larger when the pressure of the other source of fluid under pressure is below a predetermined amount.

36. The combination set forth in claim 35, in which the annular area of a double acting cylinder is connected to the other chamber when the pressure of the another source of fluid under pressure is above a predetermined amount.

37. The combination set forth in claim 1 in which the hydraulically controlled means is a linear hydraulic motor.

38. The combination set forth in claim 1 in which the hydraulically controlled means is a rotatable hydraulic motor.

39. The combination set forth in claim 1 in which a second source of fluid under pressure is provided, a second hydraulically controlled means operatively connected to said member, valve means in circuit between said second hydraulically controlled means and said second source, means controlled by said first hydraulically controlled means to actuate said second named hydraulically controlled means, an additional valve means controlling another source of fluid under pressure, at least one of said first two valve means controlling the actuation of the member through said additional valve means, said additional valve means being responsive to an intermediate hydraulic cylinder controlled by said first named valve means.

40. The combination set forth in claim 1 comprising a second pump operatively connected to said transmitter to deliver fluid under pressure upon rotation of said second pump by said transmitter, a second hydraulically controlled means to effect actuation of said member in either of two directions, second fluid control valve means operatively connected between said second pump and said second hydraulically controlled means, means responsive to the reactive forces produced by the resistance to rotation of the second pump by the transmitter to actuate said second valve means, and supplemental valve means responsive to another source of fluid under pressure and controlling the connections of the pump to hydraulically controlled means of differential area.

41. The combination set forth in claim 5 in which a second source of fluid under pressure is provided, a second hydraulically controlled means operatively connected to said member, valve means in circuit between said second hydraulically controlled means and said second source, means controlling said valve means and controlling said first hydraulically controlled means to actuate said second hydraulically controlled means, at least one of said first two valve means controlling the actuation of the member through said additional valve means, said additional valve means being responsive to an intermediate hydraulic cylinder controlled by said first named valve means, and supplemental valve means responsive to another source of fluid under pressure and controlling the connections of the pump to hydraulically controlled means of differential area.

References Cited in the file of this patent UNITED STATES PATENTS 2,392,543 Mercier J an. 8, 1946 2,763,990 Mercier Sept. 25, 1956 

